Compound gas pressure regulator



Feb. 20, 1934.

G. M. DEMING Filed June 30, 1951 2 Sheet's-Sheet l INVENTOR Feb. 20,1934. 5. M. DEMING COMPOUND GAS PRESSURE REGULATOR Filed June 30, 1931 2Sheets-Sheet 2 INVENTOR um,

ATTORNEY Patented Feb. 20, 1934 v UNITED STATES PATENT OFFICE 1,948,021COMPOUND GAS mesons nmomron George M. Dem l, East Orange, N. J.,assignor to Air Reduction Company, Incorporated, New York, N. Y., acorporation of New York Application June 30, 1931. Serial No. 547,851 8Claim. (CI. 50-23) This invention-relates to apparatus for regulatandclamps the second-stage diaphragm 13 ing the pressure or a gas, forexample oxygen as against an internal shoulder 14 at the base of usedwith welding and cutting equipment, Th said rim. This construction ofthe body and its invention relates more particularly to regulators beckcap and bonnet, i accordance Wi w i h 5 in which the pressure is reducedin two succesthe hack cap screws on the Outside o he y sive stages in itof apparatus. whereas the bonnet screws on the inside, aids in oneobject or the invention is to secure a high Obtaining a sh rt l n th f rt mp und unit degree of compactness by a special construction WhileStill leaving ample Space 011 h mi -p rand combination or parts forminga unit or this ticn 0f the body n which t f rm the conneccharacter.Another object is to provide a contioh hOSSeST15, 16 and 7- structionwhich is economical to manufacture. The flph agms are pr y 1 fabric-re-Other objects are facility of access to working 1hfi'heed rubberparts,and this without the breaking of high pres- The boss 15 receives the -Pe su e n et sure joints or the consequent necessity of sealingconnection the boss 1 r iv th hi hlit up metal to metal joint pressuregauge 19, and the boss 1'7 receives the F o th standpoint of operation,t obj t low-pressure outlet connection 21 and the loware very preciseand uniform regulation up to the Pressure gauge end point, very low endpoint and saving of cylin- The heck cap ins a h li al interta e der gasresulting from the lowering of the end control spring 23 fi d tension,which bears at 29 point. Another object is the avoidance of humits endsagainst the center of the cap ming and against a back plate .24 of thefirst-stage These and other objects and features 01' the diaphragm. Thisspr n determines a fix d and invention will be understood from thedrawings, relatively high intermediate P essure in the inshowing thepreferred embodiment of the inventerstege cavity 6- 5 tion, and from thebody of the specification. The bonnet 11 contains an edillstehleleglllet- 30 In th said drawings; ing spring 25, which bears at itsouter end against Fig. l is an axial section through a pressure a button25 and at its inner end st a owregulator embodying the invention;Pressure diaphragm plate the att r i g Fig. 2 is a cross-section takenapproximately fixed to this diaphragm y a headed Stud 28am! 30 on theirregular line 2-2 indicated in Fig. 1; a hut A manual adjusting Screw30' has Fig 3 is a plan view looking t t e interstage threadedengagement with the end of the honside of the regulator, with the backcap and n and bears against h Spring butto 26 t0 diaphragm removed; I iadjust the delivery pressure of the gas which Fig. 4 is a view, partlyin section and partly in Passes from the Outlet 35 elevation, showing asignal button and a form of Beneath the Seeohd Stage p m, a d bemeansfor hglding it in t position shown in tween it and the web wall 3, isthe low-pressure Fig. l; and cavity 31;

5 is a plan view of t holding Washer A high-pressure nozzle .32 isscrewed from the lustrated in Fig. 4, before the prongs have beeninter-Stage cavity 6 into a Socket 33 f he W b 0 opened I wall, adjacentone side 01 the regulator. The The body 2 of the regulator'is generallycircu socket 33 is connected by a passage 34 with the 1 t has t may betermed an internal web socket of the inlet connection boss 18, andanwall 3, forming a division between the two stages other Passage 35connects the Passage 34 W h of the compound regulator, and two annularrims the Socket 0f the -m' gauge OSS 16.

45 4 and 5 at its opposite ends. The rim 4 surrounds The lip of thenozzle 32 proieets into e nterthe inter-stage cavity 6, which is thereduced- -8 cav y Where it ccects with a face of a pressure h b of thfirst; stage of t reguvalve element 36 of the kind known as a seat.lator. This rim has a screw-thread on the out- Th s seat, w h is ra y oc mpa atively side, whereas the rim 5 is screw-threaded on the a dmateriel, is held in recess in t e Short 50 inside. A back-cap 7 has aperipheral flange 8 arm of a lever 3'7 01 the first order and is pressedwhich screws on the outside of the rim 4, and the by simple leverageagainst the nozzle lip. This margin of the first-stage diaphragm 9 isclamped lever is fulcrumed on rounded protuberances 38, between the endof said rim and an internal which work in conical recesses in the bottomor shoulder 10 of the cap. Another cap or bonnet the cavity, asdisclosed in my application Serial 11 has a flange 12 which screwsinside the rim No. 243,062, filed December 28, 1927, which ma- 1m turedinto Patent 1,839,837, Jan. 5, 1932, the friction of this fulcrumserving to suppress humming. A plate compensating spring 39 of more orless crescent form is secured to the bottom of the inter-stage cavity bya screw 40, and its tips 41 press against ears 42 projecting from thesides of the seat-holding portion of the lever, also as disclosed in thesaid application. The end of the long arm of the lever has a roundedcrest 43 bearing against a central face plate 44 associated with thediaphragm 9. The lever is not fastened to the diaphragm.

The first stage of the compound regulator corresponds to a regulator ofthe direct type, more specifically a lever-type regulator; Thecompensating spring 39 presses the seat 36 against the nozzle 32 inopposition to the high inlet pressure acting through the orifice of thisnozzle. The non-adjustable inter-stage control spring 23, whichcorresponds to the regulating spring of a regulator or reducing valve ofthis class, acts through the diaphragm against the lever, and, beingsuperior to the compensating spring, will cause the seat to separatefrom the nozzle whenever the pressure in the inter-stage cavity tends tofall below the value for which the control spring is set. Whenever, onthe contrary, the inter-stage pressure tends to increase, the controlspring is overcome and the compensating spring urges the seat toward thenozzle.

The orifice 45 of the second stage of the regulator opens through thecenter of the web wall 3 of the body at the bottom of an internallythreaded socket 46 which extends in from the inter-stage cavity 6. A lip4'7 projects rearwardly around said orifice, constituting a nozzle.

A thimble 43 is screwed hand-tight into the socket 46. Thesescrew-threads do not have to be gas-tight, so that the provision of areadily removable thimble is permissible. This thimble guides 'arectilinearly movable valve element of the second stage of the compoundregulator. This valve element comprises a seat 49, preferably of softrubber, the face of which coaets with the nozzle 47, and a seat-holder50. The head of the seat-holder is to be understood as being of apolygonal or equivalent shape, which gives it a sliding bearing in thecylindrical inner wall of the thimble while permitting gas to passaround it. A stem 51 extending rearward from the head is also guided ina hole 52 in the rear end of the thimble. A post 53 projects forwardfrom the head of the seat-holder, through a central opening in the seat49, and through the orifice 45, to coact with the head of the stud 28 ofthe second-stage diaphragm 13. This valve element is not fastened to thediaphragm. A marginal spring 54 inside the thimble exerts expansiveforce between the head of the seat-holder and the rear end of thethimble to urge the seat against the nozzle. Openings 55 in the thimbleadmit gas from the inter-stage cavity 6.

A passage 56 permits gas to pass from the lowpressure cavity 31 to theinterior of the boss 1'7, whence it goes to the distributing line.

As thus described and illustrated, the second stage of the compoundregulator will be recognized as being similar to a regulator of theinverse type, in which the valve element closes with the higherpressure, instead of against the higher pressure as in regulators of thedirect type.

The pressure of the adjustable\ regulating spring 25 acting through thediaphragm 13 against the thrust projection 53 of the seat-holdor 50moves the seat 49 away from the nozzle 47 against the pressure of thegas in the interstage cavity 6 and against the pressure of the marginalspring 54. When the gas passing through the orifice 45 into thelow-pressure cavity 31 builds up the intended delivery pressure in thiscavity, such pressure acting on the diaphragm overcomes the regulatingspring 25 and permits the valve to close under the inter-stage pressureand/ or the pressure of the marginal spring. When the delivery pressuretends to decrease, the spring 25 acting through the diaphragm againunseats the valve element,.permitting more gas to pass into thelow-pressure cavity.

Important advantages result from employing in the first stage of theregulator the features of the herein described direct-type regulator ofthe lever class, and further advantages are obtained by combining afirst stage of this kind with a construction for the second stage of thegeneral nature which has been described. One of the advantages is asubstantial gain in compactness for the entire unit. It will be observedthat it has been possible to accommodate the nozzle, seat and lever ofthe first stage, and the seat-holder and guide thimble of the secondstage, 100 within a quite narrow cross-sectional zone, at the same timeallowing for ample cavities 6 and 31 between the irregularly formed webwall 3 and the diaphragms 9 and 13. In consequence, the distance betweenthese diaphragms is very short. 105

Other advantages have to do with excellence of total regulation andlowering of the end point. In the first or high-pressure stage thedisplacements of the seat 36 toward and from the nozzle 32 are verysmall, whereas in the second or lowpressure stage the seat displacementsare comparatively large. In consequence, spring stiffness in the firststage has little influence, whereas in the second stage it is animportant factor.

In a regulator of the direct type the delivery 115 pressure or reducedpressure tends to droop with decreasing cylinder or supply pressure,whereas in a regulator of the inverse type the delivery pressure tendsto rise with decreasing supply pressure. When operating on relativelyhigh 12( pressure, so that seat displacement is small and springstiffness is not of moment, the delivery pressure of a direct typeregulator will droop materially less than the delivery pressure of aninverse type regulator will rise. Consequently, l2v the direct-typefirst stage regulation of the pres- 1 ent compound regulator gives asnearly uniform inter-stage pressure as can be obtained. Furthermore,since this stage operates on high pressure, suflicient dampeningfriction can be introduced, as by means of the fulcrum protuberances 38,to insure against humming, without impairing the regulation.

In the second stage, the relatively large amplitude of the movements ofthe seat-holder and 13 diaphragm brings spring stiffness into play.Whereas in a direct type regulator spring stiffness will augment thetendencyof the delivery pressure to fall on with dropping supplypressure, in an inverse type regulator it will work against the tendencyof the delivery pressure of such a regulator to rise. Since theoperation of the second stage of a compound regulator involvesrelatively large seat displacement and exercises the springs, theinverse type of regulation is the most advantageous for this stage, andin combination with direct type regulation in the first stage givesalmost perfect total regulation. Another advantage of compoundregulators em- 1 poses the lever, seat and nozzle of the bodying thiscombination is the marked lowering of the end pointof total regulation.

Furthermore, whereas the action of the direct, lever-type, first stagecan be sufficiently dampened to prevent humming without detriment to itsperformance, that would not be true of the same type of regulation ifapplied to'the second stage. On the other hand, inverse regulation inthe second stage is free of humming. Consequently, the combination oflever type regulation in the first stage and inverse type regulation inthe second stage not only provides the best resultant regulation butalso eliminates the humming nuisance.

In event of seat-leak in the first stage of the regulator, pressurewould build up in the interstage space 6 and could not be relieved intothe low pressure cavity 31, because the valve element of the secondstage closes in the direction in which the pressure acts. Theinter-stage cavity not being provided with a pressure gauge, thefirst-stage diaphragm 9 might therefore be ruptured unnecessarily. Toavoid this, a simple signaling device is provided, which is displayed orbrought into prominence by the action of the diaphragm 9 when the latteris fiexed outward beyond the position which it occupies when the seat 36is closed against the nozzle 32.

The form of this signal or indicator can be varied. It preferablyconsists of a button 66 occupying an opening 5'7 in the center of theback cap 7 and normally even with the outer surface. This button has aninwardly projecting stem 58 opposed to the back plate 24of thediaphragm, but not ordinarily displaced by the latter. When thediaphragm is pushed out abnormally, the button is protruded. The signalthus given may be made more pronounced by coloring the sides of thebutton red, these sides being ordinarily concealed by the cap. Aninternal fiange 59 on the cap at the outer end of the opening 5'7 and anexternal stop flange, 60 on the inner end of the button keep the signalbutton from coming entirely out of the case. A washer 61 held betweenthe spring 23 and the inside of the back cap, encircling the stem 58 andprovided with a number of rearwardly bent, inclined prongs pressingresiliently against the sides of the stem, keeps the signal buttonreliably in place but permits the button to be pushed outward by thediaphragm. Other forms of non-positive holding means may be provided forthis purpose. The signal holding means enables the button to be pushedin again to retained position if the seat obstruction should clearitself, making it unnecessary to take off the back cap to clean orreplace the seat.

A signal device of this general character may be applied with equaladvantage to a singlestage regulator or reducing valve not provided witha low pressure gauge.

The ease of inspection and removal of the working parts of the regulatorwill be apparent. Removal of one cover, namely the back-cap 7, ex-

first stage and the thimble containing the seat and seatholder of thesecond stage. The back cap having been removed. the only operationrequired to remove the high-pressure seat 36 is to unscrew the screw 40,which permits the compensating spring 39, the lever 37 and the seat tobe taken out. The low pressure seat 49 and its seatholder can beextracted by merely unscrewing the thimble 48. No high pressure joint isopened in connection with these operations and no metal to metal jointhas to be sealed when the parts are replaced and the back cap screwed onagain.

The operation of the regulator is as follows: High pressure gas from thecylinder or other source enters at 15, and after passing through afilter 70, enters the nozzle 32. The high pressure seat 36 being heldaway from the nozzle by the inter-stage control spring 23, the gas flowsthrough the nozzle and into the inter-stage cavity 6. There the pressurebuilds up until the force against the diaphragm overcomes the force ofthe control spring and the seat closes against the nozzle under theaction of the compensating spring 39. If the adjusting screw it is nowturned in, compressing the regulating spring 25, the gas after flowingthrough the ports 55 of the guide thimble 48 and past the seat holder50, can discharge through the orifice 45 into the low pressure cavity31, and thence out through outlet 21.

While the preferred embodiment of the invention has been described indetail, it will be understood that various changes are permissiblewithin the general scope of the invention.

I claim:

1. A pressure regulator having a body formed with an internal wall andwith an inter-stage cavity and a low-pressure cavity at opposite sidesof said wall, first-stage and second-stage diaphragms covering saidcavities, caps applied to opposite sides of said body, springs beneathsaid caps bearing on said diaphragms, an orifice nozzle in said internalwall projecting into said interstage cavity, a valve element having aface coacting with the terminal lip of said nozzle, a lever of the firstorder in said inter-stage cavity, said lever having a long arm and ashort arm, said long arm bearing against the under side of thefirst-stage diaphragm, and said short arm acting by simple leverage onsaid valve element, a compensating spring acting on said lever to urgesaid valve element against said lip, said internal wall having anorifice through whi h gas passes from the inter-stage cavity to thelow-pressure cavity, a projecting nozzle lip at the inlet end of saidorifice, a valve element having a face coacting with said nozzle lip, aguide in said wall in which this latter valve element is truly guided, athrust element extending through this orifice between this valve elementand the second-stage diaphragm, and a spring urging this valve elementagainst the inlet of this orifice.

2. A pressure regulator having a body formed with an internal wall andwith an inter-stage cavity and a low-pressure cavity at-opposite sidesof said wall, first-stage and second-stage diaphragms covering saidcavities, caps applied to opposite sides of said body, springs beneathsaid caps bearing on said diaphragms, means providing an orifice throughwhich gas enters the interstage cavity, a valve coacting with the outletof said orifice, a lever associated at one end with said valve elementand bearing at the other end against the under side of the first-stagediaphragm, a compensating spring acting on said lever, said internalwall having an orifice through which gas passes from the inter-stagecavity to the low-pressure cavity, a valve element coacting with theinlet of this latter orifice, a guide in said wall in which this lattervalve element is truly guided, a thrust element extending through thisorifice between this valve element and the under side of thesecond-stage diaphragm, and a spring urging this valve element againstthe inlet of this orifice, said lever and both said valve stage cavityon removal of a single cap and the first-stage diaphragm.

3. A pressure regulator having a body formed with an internal wall andwith an inter-stage cavity and a low-pressure cavity at opposite sidesof said wall, first-stage and second-stage diaphragms covering saidcavities, caps applied to opposite sides of said body, means providingan orifice through which gas enters the inter-stage cavity, a valveelement coacting with the outlet of said orifice, a lever associated atone end with said valve element and bearing at the other end against theunder side of the first-stage diaphragm, a compensating spring acting onsaid lever, said internal wall having an orifice through which gaspasses from the inter-stage cavitytothe low-pressure cavity, a valveelement coacting with the inlet of this latter orifice, a formation onsaid wall against which this latter valve element seats, said wallhaving a socket, a thimble inserted in said socket from the inter-stagecavity and removable from said wall and from said formation on the wall,said valve element being guided in said thimble, and a spring in saidthimble urging said valve element against said formation, said lever andits valve element, and said thimble and its valve element, being readilyremovable from the inter-stage cavity on removal of a single cap and thefirst-stage diaphragm.

4. A pressure regulator having a one-piece body formed with an internalwall, an inter-stage cavity and a low-pressure cavity at opposite sidesof said wall, and oppositely projecting annular rims, inlet and outletconnections on a. central zone of said body, a first-stage diaphragmseated on top of one of said rims, a cap screwed on the outside of thisrim and clamping the margin of said diaphragm,,a diaphragm seat formedbelow the top of the other rim, a second-stage diaphragm seated on thisseat, a cap screwed on the inside of this rim and clamping the margin ofthe second-stage diaphragm, springs beneath said caps bearing on saiddiaphragms, an orifice nozzleset in said internal wall and projectinginto said inter-stage cavity, said nozzle being in communication withsaid inlet connection, a valve element coacting with the terminal lip ofsaid nozzle, a lever associated at one end with said'valve element andbearing at the other end against said first-stage diaphragm, acompensating spring bearing against said lever, said internal wallhaving an orifice through which gas passes from the interstage cavity tothe low-pressure cavity, a valve element coacting with the inlet end ofthis latter orifice, a guide in said wall in which the latter valveelement is truly guided, a thrust element extending through this orificebetween this valve element and the second-stage diaphragm, and a springurging this valve element against the inlet of this orifice, said leverand both of said valve elements being removable from said inter-stageelements being readily removable from the intercavity on removing theback cap and the firststage diaphragm.

5. A pressure regulator having a body formed with an internal wall andwith an inter-stage cavity and a low-pressure cavity at opposite sidesof said wall, first-stage and second-stage diaphragms covering saidcavities, caps applied to opposite sides of said body, springs beneathsaid caps bearing on said diaphragms, an orifice nozzle in said internalwall projecting into said interstage cavity, a valve element having aface coacting with the terminal lip of said nozzle, a lever of the firstorder in said inter-stage cavity, said lever being fulcrumed on saidinternal wall and freely separable therefrom, one arm of said leverbearing against the under side of the first-stage diaphragm and theother arm acting by simple leverage on said valve element, acompensating spring acting on said lever to urge said valve elementagainst said lip, said internal wall havin an orifice through which gaspasses from the inter-stage cavity to the low-pressure cavity, aprojecting nozzle lip on said wall at the inlet end of said orifice, aone-piece thimble inserted in said wall from the inter-stage cavity sideand removable from said wall and from said lip on the wall, a valveelement truly guided in said thimble and having a face to coact withsaid lip, and a spring confined between this latter valve element andthe integral rear end of said thimble to urge the valve element againstsaid lip, said lever, said thimble and both valve elements being readilyremovable from the inter-stage cavity on removal of a; single cap andthe first-stage diaphragm.

6. A pressure regulator having a body formed with an internal wall andwith an inter-stage cavity and a low-pressure cavity at opposite sidesof said wall, first-stage and second-stage diaphragms covering saidcavities, caps applied to opposite sides of said body, springs beneathsaid caps bearing on said diaphragms, an orifice nozzle in said internalwall projecting into said interstage cavity, a valve element having aface coacting with the terminal lip of said nozzle, a lever of the firstorder in said inter-stage cavity, said lever having a long arm and ashort arm, said long arm bearing against the under side of thefirst-stage diaphragm, and said short arm acting by simple leverage onsaid valve element, a compensating spring acting on said lever to urgesaid valve element against said lip, said internal wall having anorifice through which gas passes from the inter-stage cavity to thelow-pressure cavity, a valve element coacting with the inlet end of saidorifice, a guide in said wall in which this latter valve element istruly guided, a thrust element extending through this orifice betweenthis valve element and the second-stage diaphragm, and a spring urgingthis valve element against the inlet of this orifice.

GEORGE M. DEMING.

